Tag Archives: Bahamas Shells

CONCH QUEST: ABACO’S MOST VERSATILE GASTROPOD

The conch. Such a fascinating gastropod, and with so many uses both culinary and decorative. In certain cultures, religiously significant. A rudimentary musical instrument for a shell. And did I mention delicious?

Live conchs enjoy motoring around uninhibitedly on the sea floor, keeping an eye out…

Conchs also enjoy racing each other…

“Eat my dust…”

Conch Pearl – one of the rarest natural pearls in the world

A conch spiral close-up

Conch shells just lie around the place at Sandy Point

Conchs are widely used for serving cocktails or as ashtrays in the best beach bars*

*This is a lie. Sorry about that. I meant to say “make prefect table decorations”

TAKING A CLOSER LOOK: ROCK POOLS ON ABACO

Here’s a promising-looking rocky outcrop a short distance south of Crossing Rocks. The action of the sea over centuries has eroded and pitted it – ideal for the formation of pools in which marine life can thrive.

Time to clamber up to see if the theory holds good… the prospects are encouraging. There are certainly plenty of sea urchins here.

Let’s zoom in on the nearest pool. There are clearly 2 different-coloured sea urchins here, but I’m not sure if that’s an age thing or a species thing.

Apart from the sea urchins, there are some shells and other things that need a closer look…

At the bottom of these photos, you can see that a zebra-marked nerite is quite happy to share a hole with an urchin. There are two brownish accretions on or in the rock. My tentative suggestion is that these are the shells of some sort of worm, perhaps petaloconchus.

UPDATERick Guest helpfully comments “Yes, it’s quite the invertebrate hotel mostly due to the urchin’s talent for scouring out protective “rooms”. Of interest is the Magpie shell (Livona pica) in frames 4 and 5. The rather ubiquitous Livona’s very thick shell, (Up to 5″ diameter) and ability to withstand most attempts at removal by predators, including Homo sapiens, assures their continued presence on littoral shore lines. They are edible, but not particular tasty to my palet. All these “Condo” residents “party” at night and will even leave the rock in search of food and perhaps romance, so a flash pic of the condo at night would be an interesting contrast to a daylight shot”.

In a snug little cave (top right) just above the water-level of the pool is a primitive-looking chiton, a species that has been around for millions of years. Below, there’s a clearer image of one from a different pool. These creatures always remind me of school projects on prehistoric trilobites.

The rough rocky surfaces close to the pool are covered in shells. The stripey nerites are small, the grey shells really are miniature. They are mostly littorines/ periwinkles and perhaps ceriths, I think.

Close-up views of nerites showing their distinctive markings and spirals

SMALL SHELLS FROM CASUARINA, ABACO

The shell species below (also in the header picture) is an olive. It turns out to have potential to star in a small maritime horror movie. Capt Rick Guest, who kindly keeps an eye on my shell and other sea-related posts, writes“Interestingly, the previous occupant of the first and last shell pictured here is a major predator of the other Bivalve shells shown. The Olive shell hides under the sand by day, then emerges at night to feast upon small Bivalves, and any other available prey. One can often trace the nocturnal trails of this Olive shell in sand on calm mornings with mask and snorkel, and thrust a hand under a trails end for this fellow. When kept in an aquarium, they will consume any meat offered.” “Olive and Let Die”, maybe?

It’s time to look at another shell from Delphi. The club has glass jars displaying small shells in the Great Room. Larger shells like the ones below are displayed on shelves. The King Helmet is the largest of the helmet shells of the family Cassidae. They are found in the Western Atlantic from North Carolina through the Caribbean and the gulf of Mexico down to Brazil. They tend to bury themselves during the day, becoming active and feeding at night. In humans this behaviour is found mainly in students and in those involved in the music business and similar louche occupations.

King Helmets prey mainly on sea urchins and other echinoderms, using their foot to grip their meal. The dining arrangements are somewhat protracted. The snail makes a hole in the urchin through the combined action of a glandular secretion which is rich in sulphuric acid, while using itsRADULAto rasp and dig through the shell to get at the trapped occupant, which it gradually consumes… That’s enough about that.

I have recently featured some of the shells from the collection amassed at Delphi – see SHELLS 1 and SHELLS 2. They are kept in vases or bowls for display and examination. They may not all come from the immediate vicinity, but they are all, for sure, from South Abaco. It’s time for some more.

PINK TRIVIA SHELL

LETTERED OLIVE SHELL

COMMON SPIRULA

For further details about Spirula(e), please see the comment box where Capt Rick Guest gives a lot of fascinating info about them and related marine cast-offs. You’ll also find out which are the real prize ones to look out for…

Here are two contrasting shells from the Delphi Club collection that has been haphazardly accumulated over the last 3 years or so. The first post in this shell series was about SEA URCHINS & SEA BISCUITS

TULIP SHELLS Fasciolaria tulipa

The term ‘Tulip snail’ includes 3 related species of sub-tropical gastropod worldwide, of the genus Fasciolaria. They are medium-sized predatory molluscs that breed throughout the year in warm waters. Their reproductive lives deserve some attention, if they will pardon the intrusion.

Research by the Smithsonian Marine Station Fl. reveals that the male’s penis is to be found on the right side of its body, directly behind its head… When they mate the (larger) female stays in an upright position on the sand while the male ‘flips over’ to align the apertures of both shells, before inserting the penis into the female (RH comment: the research is not specific about precisely where the female keeps her own genitals). Once joined, snail pairs may remain locked together for up to 2 hours, even when being watched by researchers. They have plenty of stamina: mating may occur several times in one season, and individual tulip snails have been observed to mate up to 3 times in a single week. Respect!

SUNRISE TELLINSTellina Radiata

I included these pretty shells, with their striking pink radials, in an earlier postBEACHCOMBING BIVALVESThe ones shown here are larger specimens. The hinges (muscles) are very delicate, and in these shells the two halves of the shells have separated. STs are not uncommon, but these are the largest I have come across (I realised after I had taken the photos that I should have used a coin for comparison…). They grow up to about 7 cms, and these ones were that length, or very nearly so.

I can’t assist with their sex lives I’m afraid, which may well be completely conventional, dull even. However, as I discovered when I previously researched these shells, “in most countries it is illegal to bring back these shells from holidays”. To which I can only repeat my comment: Whoops!